>>16437996This. Learn to breed, OP.
If you have two parents with 3 IVs, and get a child with 4 IVs, swap it out with one of the parents. Breed until you get another 4-IV of the opposite gender (make sure they have the right IVs to cover the five you want). Then keep breeding for fives, swap the parents and breed until eventually you're rolling in 5IV pokemon and if you really have a lot of free time you can use two 5-IV parents to grind for a perfect 6-IV offspring. It's not that hard.